@article{GDZPPN002222396, title = {Minimal Coverings of Manifolds with Balls.}, journal = {Manuscripta mathematica}, volume = {29}, year = {1979}, pages = {385-416}, zbl = {0415.55001}, url = {http://dml.mathdoc.fr/item/GDZPPN002222396} }
Singhof, Wilhelm. Minimal Coverings of Manifolds with Balls.. Manuscripta mathematica, Tome 29 (1979) pp. 385-416. http://gdmltest.u-ga.fr/item/GDZPPN002222396/